I want to make this a pull chain .

you will need to go and turn off breaker.

taking it that you are referring to a petrol chain saw
the chain brake is the big lever at the top hand hold
push forward activates the brake --pull back allows the chain to run
revving the motor with the brake pushed forward will burn out the centrifugal clutch
if you have it pulled back and the chain is not running with an increase in rpm , then there may be a problem in the nclutch

You can buy it online from Hover Global. Please visit: http://www.hover.global/hercules.html

pull the chain clutch back towards the handle
it is not a chain lock but a clutch release that stops the chain from turning
pulling it back engages the clutch to drive it

Sue:

Wear gloves when handling the chain (or have a lot of band aids).
You will need a 7/16 or 1/2 inch wrench and a screwdriver. Lay the saw on its side so the bar is up. There will be two studs with nuts on them. Both nuts are the same size. Look at the front of the motor housing cover on the outside of the chain bar and you will see a screw head. Loosen the two nuts holding the bar (just a few turns) and turn the screw so the chain tightens. When you pull up on the chain at the middle of the bar the chain should not pull up more than 1/16" (one sixteenth of an inch). If the dogs on the inside of the chain pull clear of the track around the outside of the bar, the chain is too loose. Once you have the chain tension correct, tighten the two bolts, and tighten them good and tight. If the chain adjustment is correct, when you pull the chain away from the bar at the center of the bar, it should pull up about 1/16 of an inch and you should not be able to pull the dogs out of the slot around the edge of the bar. You should be able to pull the chain around the bar (as if the saw were running).

Jo:
Unplug the saw.
Lay the saw on it's side so the chain and bar are up (lay it on 4X4 blocks or something similar so the motor housing doesn't make the saw rock back and forth) Loosen the two 1/2 or 9/16 nuts... don't take them off, just loosen them a turn or two. Look toward the saw where the bar comes out (the front of the housing where the blade comes out). You will see a small screw head. Turn the screw clockwise (as if you were tightening it) As you turn that screw, the chain will tighten. Put on some gloves and pull the chain around the bar (as if the saw was running, but you are the motor). The chain should move with a little resistance. Pinch the chain at the top-middle of the bar and pull the chain up away from the bar. the chain should pull away from the bar no more than 1/16 to 1/8 inch. If you look carefully between the bar and the chain, you'll see the dogs that run in the groove in the outside circumference of the bar. None of the dogs should be fully exposed when you pull up on the chain (in other words, None of the dogs should come completely out of the bar's chain groove when you pull up on the chain. Now, tighten the two nuts on the back of the bar. Snug them down good... if the bar slips on those two nuts, the chain will come off while you are cutting.

Good luck

The lamp has on-off pull-chain switch.
You can buy replacement pull-chain switch at hardware store.
Buy the pull-chain switch that has two wires.
Buy two yellow or orange wire nuts.

Switch off breaker.
Take apart light.
Remove old pull-chain. Strip back the wires if needed, twist wires together.
Connect new pull-chain switch using wire nuts.

you need to replace the switch . which is where the chain came out

go to purchase another control switch

Unhook the master link and lay the chain in the concrete. Next, hold one end to the concrete and sort of push the chain towards the stationary end. The object is to push the chain together as opposed to stretching it apart. Mark the concrete at the location of the shortened end. Now again hold the stationary end firm and this time stretch the chain to its' fullest length. Mark the concrete again at the end of the stretched chain. If the distance between the marks is over one inch the chain should be replaced.
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Look at the teeth of both sprockets. Are the teeth rounded on the end or are the teeth forming a pointed looking end? If rounded, then the sprocket is good. If pointed, then the sprocket is bad.
Bad sprockets can ruin a good chain. The exception to the one inch rule is a chain that is rusted and no longer limber. Replace a rusted chain. Remember, always install the master link clip with the blunt end facing the direction of chain travel.
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